With the rapid development of display technology, touch panel (TP for short) is increasingly applied to the field of high-performance display due to its characteristics such as intuition, easy operation and the like.
The touch panel includes an Add On touch panel and an In Cell touch panel.
At present, the touch sensing method of the in cell touch panel is mainly based on mutual capacitance. The mutual-capacitance type in cell touch panel includes a color filter substrate and an array substrate arranged opposite to each other, wherein the touch driving electrode and the touch sensing electrode are arranged on the array substrate. The touch principle is that: when loading a touch driving signal to the touch driving electrode, a sensing voltage signal coupled by the touch sensing electrode via a mutual capacitor is detected. During this process, when a user contacts the touch panel, the electric field of a human body will act on the mutual capacitor to enable variation of the capacitance of the mutual capacitor, so that the sensing voltage signal coupled by the touch sensing electrode via the mutual capacitor is changed, and thereby a position of a contact point can be determined according to the variation of the sensing voltage signal.
As the touch sensing electrode of the in cell touch panel is arranged on the array substrate, the touch sensing electrode is positioned away from the external touch position, thus the touch sensitivity is lowered, and thereby interference and noise are generated between the display signal and the touch signal of the touch panel.
In order to solve the above problem, the touch sensing electrode is generally formed on the color filter substrate in the prior art, and a black matrix formed of metal material, an insulating layer, a color resin layer and a touch driving electrode are successively formed on the touch sensing electrode at a side of close to the array substrate. The metal black matrix can function as bridging the touch sensing electrode and the touch driving electrode, so that the touch sensitivity of the touch panel is improved. However, it is complex in the process and high in cost to manufacture the display device by using the above color filter substrate.